Background: Closed reductions of distal radial fractures are among the most common orthopaedic operations but up to 39% of fractures lose position postoperatively. This study was carried out to determine the most significant risk factors for loss of position so that high-risk patients can be identified early and their management tailored accordingly.
Methods: We retrospectively reviewed 48 consecutive children who had redisplacement of their distal radial fractures after closed reduction and compared them with 48 matched controls. Fourteen risk factors were studied and analyzed with univariate and multivariate logistic regression analysis and receiver operating characteristics analysis. These risk factors included pre-reduction and post-reduction fracture characteristics as well as 4 previously described radiological indices of plaster quality.
Results: Significant independent clinical risk factors identified were the initial radial fracture displacement [odds ratio (OR) 1.03, P = 0.001] and obliquity (OR 0.93, P = 0.006), a completely displaced radial fracture (OR 5.21, P =0.003), an ipsilateral ulnar fracture (OR 3.56, P = 0.003), residual radial displacement (OR 1.06, P = 0.009), angulation (OR 1.16, P = 0.011), and failure to achieve anatomical reduction (OR 0.18, P = 0.004). Significant radiological indices included the Padding index (OR >100, P = 0.004), Canterbury index (OR 99, P = 0.014), and 3-point index (OR 19.29, P < 0.001). Nonsignificant risk factors included the angulation of the initial radial fracture, a completely displaced ulnar fracture, plaster changes/splitting and the Cast index. The combined preoperative presence of a completely displaced radial fracture, an ipsilateral ulnar fracture and failure to achieve perfect reduction was found to be the best predictor of redisplacement (receiver operating characteristic area under the curve=0.82). This combination was found to be a better predictor of redisplacement than any of the radiological indices (receiver operating characteristic area under the curve ≤ 0.74) and it is also a more practical risk factor for the operating surgeon to use.
Conclusions: The combination of a completely displaced distal radial fracture and an ipsilateral ulnar fracture, which then cannot be perfectly reduced, was the best predictor for redisplacement. We recommend that serious consideration be given to primary wire fixation in these patients.
Level of evidence: III, prognostic.